Abstracts

Rationale: Lacosamide (LCM) is approved for adjunctive treatment of partial seizures with or without secondary generalization in European Union and United States. It acts by enhancing the slow inactivation of sodium channels. Preclinical studies have proposed, that LCM in combination with sodium channel blocking (SCB) antiepileptic drugs (AEDs) could offer additional efficacy or additional side-effects (1). Methods: Data of two large Austrian Centres of all patients with partial-onset seizures with or without secondary generalization treated between 12/2009 and 02/2011 with at least one dose of oral LCM were analyzed retrospectively. Clinical information was extracted from the patients charts. The population was divided in two groups: (1) patients with polytherapy with LCM and SCB (LCM+SCB) and (2) patients with a combination of LCM and none SCB (nSCB; LCM+nSCB).Results: Of 139 patients (80f/59m), mean age 43.6 years (SD 17.0), 58% (80/139) received LCM+SCB and 42% (59/139) patients LCM+nSCB. Overall mean duration of follow up (FU) was 16.4 months (SD 7.6), in the group of LCM+SCB 17.7 (SD 8.3) and in the group of LCM+nSCB 14.8 (6.9) months. In total 69% (96/139) of patients suffered from symptomatic epilepsy, four patients had dual pathology. Type of etiology was in 29% (29/100) of patients cortical dysplasia, 16% (16/100) hippocampal pathology, 16% tumor, 14% (14/100) vascular lesions, 9% (9/100) trauma, 6% (6/100) encephalitis. Median dose at last FU was 400mg (range 0-75). There was a significant difference regarding median number of concomitant AEDs (p<0.00001; LCM+SCB 25% 2 AEDs, 75% 3 AEDs; LCM+nSCB 25% 1 AEDs, 75% 2 AEDs) and median number of previously failed AEDs (p<0.00001; LCM+SCB 25% 4 AEDs, 75% 8 AEDs; LCM+nSCB 25% 2 AEDs, 75% 5 AEDs) between the LCM+SCB and LCM+nSCB group. No significant difference was found regarding >50% seizure reduction (LCM+SCB 27.5%, LCM + nSCB 40%) and concerning seizure freedom (LCM+SCB 14%, LCM + nSCB 22%). Twenty-six percent (21/80) of patients in the group of LCM+SCB and 10% (6/59) in the group of LCM+nSCB complained about vertigo and dizziness (p=0,018). Retention rate on 12 months was 77%. Conclusions: LCM was well tolerated by most patients in both groups (LCM+SCB; LCM+nSCB). Regarding efficacy our data suggests an additive effect of LCM+SCB and better tolerability of LCM+nSCB. Prospectively designed trials are needed.